Opencpn ( https://opencpn.org/OpenCPN/info/downloadopencpn.html ). Full navigation package that I used as the main navigation system on a circumnavigation. Doesn't come with charts but there are loads available on the net. Get it setup before you go as it may take a little while!

I'm sure there are plenty of others available but I've not felt the need to look further.

Mike

http://sailingjeannius.blogspot.com


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